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891.
M. Nováková Beat M. Riederer Vladmír Viklický Pavel Dráber 《Histochemistry and cell biology》1997,107(4):337-344
A panel of monoclonal antibodies specific of α-tubulin (TU-01, TU-09) and β-tubulin (TU-06, TU-13) subunits was used to study
the location of N-terminal structural domains of tubulin in adult mouse brain. The specificity of antibodies was confirmed
b immunoblotting experiments. Immunohistochemical staining of vibratome sections from cerebral cortex, cerebellum, hippocampus,
and corpus callosum showed that antibodies TU-01, TU-09, and TU13 reacted with neuronal and glial cells and their processes,
whereas the TU-06 antibody stained only the perikarya. Dendrites and axons were either unstained or their staining was very
weak. As the TU-06 epitope is located on the N-terminal structural domain of β-tubulin, the observed staining pattern cannot
be interpreted as evidence of a distinct subcellular localization of β-tubulin isotypes or known post-translational modifications.
The limited distribution of the epitope could, rather, reflect differences between the conformations of tubulin molecules
in microtubules of somata and neurites or, alternatively, a specific masking of the corresponding region on the N-terminal
domain of β-tubulin by interacting protein(s) in dendrites and axons.
Accepted: 11 November 1996 相似文献
892.
Conklin-Brittain Nancy Lou Wrangham Richard W. Hunt Kevin D. 《International journal of primatology》1998,19(6):971-998
In a continuation of our study of dietary differentiation among frugivorous primates with simple stomachs, we present the first comparison of differences in dietary macronutrient content between chimpanzees and cercopithecine monkeys. Previously we have shown that chimpanzee and monkey diets differ markedly in plant part and species content. We now examine whether this diet diversity is reflected in markedly different dietary macronutrient levels or the different feeding strategies yield the same macronutrient levels in their diets. For each primate group we calculated the total weighted mean dietary content of 4 macronutrients: crude lipid (lipid), crude protein (CP), water-soluble carbohydrates (WSC), and total nonstructural carbohydrates (TNC). We also calculated 4 fiber fractions: neutral-detergent fiber (NDF), which includes the subfractions hemicellulose (HC), cellulose (Cs), and sulfuric acid lignin (Ls). The HC and Cs are potentially fermentable fibers and would contribute to the energy provided by plant food, depending on the hind gut fermenting capacity of the individual primate species. The chimpanzee diet contained higher levels of WSC and TNC because during times of fruit abundance the chimpanzees took special advantage of ripe fruit, while the monkeys did not. The monkey diets contained higher levels of CP because the monkeys consumed a constant amount of leaf throughout the year. All four primate species consumed diets with similar NDF levels. However, the chimpanzees also took advantage of periods of ripe fruit abundance to decrease their Ls levels and to increase their HC levels. Conversely, the monkey diets maintained constant levels of the different fiber fractions thoughout the year. Nevertheless, despite these differences, the diets of the 4 frugivores were surprisingly similar, considering the substantial differences in body size. We conclude that the chimpanzee diet is of higher quality, particularly of lower fiber content, than expected on the basis of their body size. 相似文献
893.
Summary Monoclonal antibodies able to recognize single antigenic determinants are a powerful tool for the study of immunological heterogeneity of antigens. In this paper we have used a monoclonal antibody against the -subunit of pig brain tubulin (TU-01) to investigate the immunoreactivity of tubulins from mammals, avians, amphibia, echinodermata, plathelmints, slime moulds and protozoa. Immunoreactivity was detected using immunoblotting and indirect immunofluorescence of isolated cells. Our results show that the antigenic determinant recognized by the TU-01 antibody is present in all metazoan tubulin tested and among the eukaryotic microorganisms only in the flagellateTrichomonas vaginalis. Indirect immunofluorescence also reveals that not allTrichomonas microtubules are stained by TU-01 antibody indicating the presence of different tubulins within a single cell. This results are consistent with the multitubulin hypothesis (Fulton andSimpson 1976). 相似文献
894.
Kengo Funakoshi Tetsuo Kadota Yoshitoshi Atobe Masato Nakano Richard C. Goris Reiji Kishida 《Cell and tissue research》1999,298(1):45-54
To examine the presence of nitric oxide synthase (NOS) in the sensory system of the glossopharyngeal and vagus nerves of teleosts, nicotinamide adenine dinucleotide phosphate diaphorase (NADPHd) activity and immunoreactivity for NOS were examined in the puffer fish Takifugu niphobles. The nitrergic sensory neurons were located in the ganglia of both the glossopharyngeal and the vagal nerves. In the vagal ganglion, positive neurons were found in the subpopulations for the branchial rami and the coelomic visceral ramus, but not for the posterior ramus or the lateral line ramus. In the medulla, nitrergic afferent terminals were found in the glossopharyngeal lobe, the vagal lobe, and the commissural nucleus. In the gill structure, the nitrergic nerve fibers were seen in the nerve bundles running along the efferent branchial artery of all three gill arches. These fibers appeared to terminate in the proximal portion of the efferent filament arteries of three gill arches. On the other hand, autonomic neurons innervating the gill arches were unstained. These results suggest that nitrergic sensory neurons in the glossopharyngeal and vagal ganglia project their peripheral processes through the branchial rami to a specific portion of the branchial arteries, and they might play a role in baroreception of this fish. A possible role for nitric oxide (NO) in baroreception is also discussed. 相似文献
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899.
Dawson Ian K. van Breugel Paulo Coe Richard Kindt Roeland van Zonneveld Maarten Lillesø Jens-Peter B. Graudal Lars Muchugi Alice Russell Joanne Jamnadass Ramni 《Tree Genetics & Genomes》2017,13(4):1-17
Tree Genetics & Genomes - Forest and woodland landscape restoration is a key undertaking of renewed interest for forestry and conservation practitioners, but is hampered by the lack of... 相似文献
900.
Diana Stralberg D. Richard Cameron Mark D. Reynolds Catherine M. Hickey Kirk Klausmeyer Sylvia M. Busby Lynne E. Stenzel W. David Shuford Gary W. Page 《Biodiversity and Conservation》2011,20(1):19-40
Conservation of migratory shorebirds and waterfowl presents unique challenges due to extensive historic loss of wetland habitats, and current reliance on managed landscapes for wintering and migratory passage. We developed a spatially-explicit approach to estimate potential shorebird and waterfowl densities in California by integrating mapped habitat layers and statewide bird survey data with expert-based habitat rankings. Using these density estimates as inputs, we used the Marxan site-selection program to identify priority shorebird and waterfowl areas at the ecoregional level. We identified 3.7 million ha of habitat for shorebirds and waterfowl, of which 1.4 million ha would be required to conserve 50% of wintering populations. To achieve a conservation goal of 75%, more than twice as much habitat (3.1 million ha) would be necessary. Agricultural habitats comprised a substantial portion of priority areas, especially at the 75% level, suggesting that under current management conditions, large areas of agricultural land, much of it formerly wetland, are needed to provide the habitat availability and landscape connectivity required by shorebird and waterfowl populations. These habitats were found to be largely lacking recognized conservation status in California (96% un-conserved), with only slightly higher levels of conservation for priority shorebird and waterfowl areas. Freshwater habitats, including wetlands and ponds, were also found to have low levels of conservation (67% un-conserved), although priority shorebird and waterfowl areas had somewhat higher levels of conservation than the state as a whole. Conserving migratory waterfowl and shorebirds will require a diversity of conservation strategies executed at a variety of scales. Our modeled results are complementary with other approaches and can help prioritize areas for protection, restoration and other actions. Traditional habitat protection strategies such as conservation easements and fee acquisitions may be of limited utility for protecting and managing significant areas of agricultural lands. Instead, conservation strategies focused on incentive-based programs to support wildlife friendly management practices in agricultural settings may have greater utility and conservation effectiveness. 相似文献